Thermal power plant



Sept. 12, 1939.

I w. KARRER THERMAL POWEfi PLANT 4 Sheets-Sheet 1 Filed June 25, 1936 Werner K rrer 3%- Sapi. E2, 193%. w; KARRER THERMAL POWER PLANT Filed Jime 25, 1936 {Sheets-Sheet? Sept. 12, 1939. I KARRER 2,172,708

THERMAL POWER PLANT Filed June 25, 1936 4 Sheets-Sheet 3 Sept. 12, 1939. w. KARRER I THERMAL POWER PLANT 4 Sheets-Sheet 4 Filed June 25', 1936 Wern'er Kan-re? Patented Sept; 12, 1939 UNITED sTATEs PATENT OFFICE 2,172,708 THERMAL POWER PLANT Werner Karrer, Zurich, Switzerland Application'June 25, 1936, Serial No. 87,290

In Switzerland July 1, 1935 6 Claims. (Cl. 6059) The present invention has for its object a thermal power plant which by the use of rotary power engines provides efliciencies substantially superior to the efficiencies of rotary power plants which are known at the present time.

For this purpose, at least a part of the pres-' haust heat of the power engine is transferred to the power medium in a constant volume chamher by heat exchange.

The invention therefore has for an object to provide a plant which will operate in such a manner that some space or chamber is supplied 20 intermittently with a power medium in such a manner that said space or chamber receives the heat exchange from the outside while it is shut off, so that the power medium contained in said space or chamber is thereby subjected to an in- 5 crease in pressure as well as temperature; when the power medium has obtained a predetermined pressure, it is discharged or at least partly discharged to a rotary power machine where it is converted into mechanical energy. This cycle 30 of operations: intermittently charging a chamber, effecting the heat exchange and discharging the material from the chamber is repeated at a desired frequency, by means of valves controlling the filling and emptying of said chamber. 35 The entire device effecting the heat exchange between the heat emitting carrier and that medium which is to be heated while its volume is to be maintained constant, shall be called hereinafter heat exchanger. 40 The combustion always takes place in a preferred construction of the invention after pre heating, insofar as warm exhaust air of the machines is used directly as combustion air or warm exhaust air is used as fuel. The combustion is 45 carried out under constant volume and the material is preferably preheated by heat exchange and in thestep at least a portion of the heat loss may also be transferred. After the material to be burned has attained a predetermined pres- 50 sure and a predetermined temperature, it is ignited and burned. This ignition and combustion may again increase the pressure as well as the temperature before the expansion in the turbine itself takes place. 55 A compressor may be added for the purpose When a predetermined of pre-compressing mechanically that power medium which is to be charged into the heat exchanger and the pressure-drop corresponding to the precompression may be effected in a separate power engine which is charged continu U ally.

It is also quite possible to mix a plurality of power mediums. Intermediary heating or withdrawal of heat also'is feasible. The heat for instance may be withdrawn at various points of the entire plant for heating purposes or working purposes, or it may be withdrawn for being surrendered to a steam power system.

Other objects of the invention will in part be obvious and in part be pointed out hereinafter.

To the attainment of the aforesaid objects and j ends the invention still further resides in the novel details of construction, combination and arrangement of parts, all of which will be first fully described in the following detailed description, and then be particularly pointed out in the appended claims, reference being had to the accompanying drawings, in which:

Fig. 1 is a view, largely diagrammatic and partly in section, of one embodiment ofthe invention.

Fig. 2 is a view, largelyhdiagrammatic and partly in section, of a second. embodiment of the invention;

Fig. 3 is a view, similar to Figs. 1 and 2, of" a third embodiment of the invention.

Fig. 4 is a view, similar to Figs. 1, 2 and 3, of a fourth embodiment of the invention; Fig. 5 is a view, similarto Figs. 1, 2, 3 and 4,

of a fifth embodiment of the invention.

Fig. 6 shows another embodiment of my invention.

Fig. 7 is a view, similar to Figs. 1, 2, 3, 4, 5, 6, of a seventh embodiment of the invention.

Fig. 8 is a view, similar to Figs. 1, 2, 3, 4, 5, 6, 7, 40 of an eighth modification of the, invention.

In Fig. 1, I indicates the combustion chamber. Air is introduced into this chamber through the conduit 2, fuel through the pipe 3. The combustion gases flow through a conduit H to the heat exchanger 4 and pass within this exchanger through the chamber 5, leaving it by the pipe 6. The gases pass about at least a portion of that closed space or chamber 7. The chamber 1 is intermittently closed and-opened by the valves 8 and 9 respectively.

Both the valves 8 and!) can be actuated in any manner, known per se, for instance, by cams Ill and H0 driven by shafts II and Ill, and acting upon the rollers l2 and H2 mounted on the shafts i l9 and 9 of valves 9 and 9 respectively. Air is fed to the'chamber I by a pipe It.

The heated, and by heat reception, compressed air contained in the chamber 1 will then flow from chamber] to the air turbine l5 and in this engine at leasta portion of the energy is converted into mechanical energy. The exhaust air how-,

sustain the combustion and is returned to the.

combustion chamber I by pipe 2. The gases of combustion passingthrough the heat exchanger 4 transmit heat to the motive medium in the chamber 1 and escape as waste gases into the atmosphere by pipe 6. In the chamber 1 the air is introduced intermittently by valve 8 ar-.

ranged in the pipe l6 and is heated while the volume is kept constant or nearly so (as described wlth reference to Fig. l) "when a certain predetermined pressure is attained, valve 9 opens and the working medium passes to the air turbine l5, where work is done byexpansion.

A portion of the exhaust air oi the air turbine I9 is used as air for combustion and is led by a pipe 19 into the combustion space 29. The gases of combustion transmit, by means of the exchanger 2|, heat to the air which is within the chamber 22. The volume or the air so heated is kept constant. Air is introduced into chamber 22 intermittently and'by means of the pipe 23. The rilling and emptying of chamber 22 is controlled by the valves 24 and 29, similar to the valves 9 and 9 controlling chamber 1 as shown with respect to Fig. 1. The air is led by a pipe 29 to expand inthe air turbine 21 after a certain pressure has been attained owing to the heating the air in the chamber 22 by keeping the volume constant or nearly so. The remaining heat of the air, escaping from the air turbine 21 may beiurther made use of, for instance in the steam boiler 29 of any known construction, to which the air is led by a conduit 29. The steam generated therein is used to iced a steam turbine 99. The steam passes through a condenser 9| and the condensed steam is returned to the boiler by the pump 92.

Instead of air any other heat carrier may be prising the elements I, 1, it. If the heat carrier is not a combustible gas the heat remaining in the motive medium after the first rotary engine would have to be absorbed by air or by any other combustible gas. the eiiiciency and would make the plant more costly. v

In allthe following to the heat exchanger 4. The gases transmit heat to the air within the chamber I which air prevililsly has *been compressed from the initial pressure P. to the pressure P1 by a-compressor 92.

The potential energy of the. gases escaping from the heat exchanger by the pipe 9 is converted in the gas turbine 99 into mechanical work. The

Such a method would reduce i examples the intermittent filling and emptying of chamber 1 may be concompressed air inclosed in the chamber I is lieated at a constant volume. "The, pressure .01 the air thereby increases, say, to P2. The motive medium is red intermittently into the ,air turblue. I! by a pipe l9. Expansion takes place in the said turbine,the drop equals P2 to P1. Part of the exhaust air 0! the air turbine l is used as air for combustion in the combustion chamber i. Part thereof passes directly into the continuous current air turbine 94, in which the energy of the compressed air is converted into work. The remaining air escapes through the exhaust pipe 99 into the atmosphere.

Exhaust gases and exhaust air which have a temperature exceeding that of the atmosphere may be usedto transmit heat for any purpose.

Fig. 4 illustrates still another use or the exhaust air passing from the rotary engine and which is not used for combustion purposes. Moreover it shows a modified construction of the gas turbine.

Fresh air is compressed by the compressor 32 from initial pressure P0 to the pressure P1 and fed to the-chamber I. The compressed air passes intermittently (as shown with respect to Fig. 1) on to the chamber! of the heat exchanger 4 through a conduit l9. Heat is transmitted to said airinthe heat exchanger. the air beinglkept at a constant volume. The pressure rises up toPz. The compressed and-heated air passes now intermittently as described with respect to Fig. 1 to the air turbine 19 through a pipe l9. One

part of. the exhaust air of the turbine I5 is used forcombustion purposes in the combustion chamber l to which fuel is ted by a pipe 9. The resulting combustion gases pass to the chamber 5' of the heat exchanger 4 and transmit part of their heat to the compressed fresh. r in the chamber I, which air is-heated under nstant volume. The products of combustion scape from the chamber 9' o! the heat exchanger 4 and are introduced in the mixing chamber by a pipe 31. They are mixed here with the residual exhaust oi the air turbine 19 and the mixture being a gas with a high surplus 01' air is passed'on through conduit 99 to" the gas turbine 99. The pressure is therein reduced from Pi to P0 by expansion, work being done in the gas turbine 99. The exhaust of the gas turbine 99 transmits a further portion 0! the heat in the chamber 9 of the heat exchanger 4 to the compressed air in the constant volume chamber I. Chamber I is intermittentiy filled and emptied by means of the used in the first described part of the plant comvalves 9 and 9 in the same manner as described with respect to Fig. l. The exhaust gases pass through pipe 9 into the atmosphere, or they may be used for any other purposes.

-.Flg. 5 shows another embodiment oi my invention wherein the air is compressed by a compressor 49 iromthe initial pressure P0 to the pressure Pi, ted to the chamber 1 of the heat exchanger 4 by means of a pipe I9 and a valve 8.

The heated medium leaves chamber 1 as soon as it has attained a predetermined pressure by a conduit l9 and valve 9 and is ted to an air turbine II. The exhaust gases are fed by a pipe Al to a continuous-current turbine 42 arranged directly behind the air turbine l5. In the continuous current turbine 42 the diflerence in pressure other part of the exhaust cases 01' the turbine 42 is led into the atmosphere by condult ll. The plant is otherwise similar to those described above. Figs. 6, 7 and 8 show embodiments in which the combustion also takes place at constant volume after the heat'has been absorbed at constant volume by heat exchange. 1

In-the plant shown in Fig. 6, I01 denotes the combustion chamber arranged in; the space between'the valves Fresh air is drawn through the conduit II into the chamber I01. The filling oi the chamber I01 is controlled by the valve 8, as described in Fig. 1. In the chamber I01 the air is heated at constant volume by a part 0! oi' the rotary engine I 5 and its pressure is brought up to P1, owing to the absorption .of heat at constant volume. Fuel is introduced into the space I01 by'the pipe 3 and this fuel is ignited. Owing to the combustion, pressure and temperature may be further increased while the volume remains constant. After attaining a predetermined pressure, for instance a pressure Pa, valve 0 opens and the space I01 is evacuated into the turbine I5, where these gases now expand and thereby do mechanical work. The pressure is reduced through this conversion into mechanical energy to the value Po. Part of the exhaust gases pass into the chamber 5 of the heat exchanger 4 and transmit heat tothe fresh 6 into the atmosphere or else to any other place, where they may be used for any desired purpose. Anotherpart oi' the exhaust gases escaping throu h pipe ll may be utilized for any other purpose. a The control of the intermittent filling and emptying oi the chamber I01 is effected by the valves 8 and 9, in the same manner as described in Fig. 1. The illustrated control of the valves 0 and 9 should, of course, be regarded merely as an example, as any desired number oi. solutions can be imagined by which the number 01 the switchings of the effect. I In Figs. '1 and 8 a similar control is shown, tor example. so that .it need not be described once more.

Fix. 7 illustrates a modified construction of the plant. Fresh air or the pressure? is passed through the compressor 40. The pressure is thereby increased to P1.

gases from the gas turbine 02 heat exchanger I which they the atmosphere.

arrangement of the combustion Fig. 8 shows another tinuous current gas turbine 02. Part oi ex- 8 and .e oi. the heat exchanger utilize the pressure drop Pr-Po.

air and escape by pip present invention may be carried into In I01 0! the heat exchanger 0 the air is brought up to 'IhepressureialistoPa.

connecticnoi eon-- ;heat partly to the air in the chamber 1-01, whichis-heated at constant volume as described in Fig. l. The pressurein I01 rises owing to the heating by exchange at constantvolume. After the exchange has been terminated, the fuel is injected 5 through the conduits 3' and is then ignited.

Owing to the combustion at constant volume, the pressure in I01 rises still more. until the valve 9 exhaust gases of the turbine I 5.

The mixture passes on to the gas turbine 42 to The gases are finally returned to the heat exchange 4 to transmitat least a part of the residual heat to the chamber 5 and pass off finally into the atmosphere. p

In all the diflerent embodiments of. my invention the chambers of the heat exchanger are al-, ternately filled and emptied. Between the filling and emptying periods the exchange of heat takes place and in some cases the combustion. WhatIwishtoclaimis:

- 1. A, method or converting heat into mechan* ical powenwhich method the purpose of increasing the pressure of the. medium by heat exchange; intermittently filling said chamber with power medium, discharging the same eachtime a predetermined pressure has discharge, at least parenergy inherent in the power medium into mechanical energy; increasing the heat of the power medium and utilizing at least a part oi'the exhaust heat of the power engine by conducting the exhaust to the outside of said closed chamber and there transferring its heat by heat exchange to the power medium insaid closed chamber.

2. The method oi.' claim 1 wherein the power medium is air, the method further consistingin a a combustible substance tothe air in said closed chamber before admitting the mixture to the power engine.

35111 a method as by an exchange or heat.

4..I'he method according toclaim 1, charac- .terized in-that, after the working medium has obtained by absorption, heat under constant volume throughh'eat'exchange irom .certain temperature and a certain corresponding pressure, there is started a combustion and thereafter the gases are caused to expand, at least,

power machine.

motive medium and in u drop due to said compression in a rotary. engine to convert the energy to mechanical work.

0. In a method as defined in claim 1, in which my oi the exhaust air 

